Process of cleaning



July 23, 1935. J. F. WAiT PROCESS OF CLEANING Filed April 12, 1930 Patented July 23, 193 5 g l UNITED STATES-PATENT oer-ice I Justin F. Wait, New York, N. Y.,' assignor to John 0. Wait, New York, N. Y.

Application April'lz, 1930, Serial No. 443,906

12 Claims. (01. as -as) I Thisprocess relates to improvementsin meth taminating substance, a multiplicity'of solvents ads of cleaning fabrics and other porous mamay be used to advantage and preferably in terial bymeans of liquid solvent. It is also 849- sequence. For example, a medium light petroplicable to methods of extraction of soluble subleum distillate seems to remove a waxy stain 5 stances from aporous material. more easily than a light petroleum distillate, 5

The common method of cleaning stains or but would itself stain the porous material where-, cloths and other porous materials usually infor a light distillate should follow a medium or volves the agitation or mixing of said cloths or heavy distillate. In this manner the final solvent material with a solvent capable of removing the wetting the fibre is easily volatilized, leaving the i0 stain or other impurities contaminating the porous material substantially free from solvent in same. In other-instances, the surface is rubbed after the process has been completed. or sponged with the solvent or cleaning agent. It is possible to clean some fabrics by using In either case the penetration of the solvent is aqueous or alcoholic solvents containing salts of limited by the, extentof diil'usion or seepage. fatty acids such as soap and like agents; High 15 Such treatment is not thorough and an apprecieconomy: may be had if such cleaning fluid is 15 able part of the liquid containing the impurity is reused. The cleaning fluid may be purified beleft in the pores and on the surface and evapoe tween cycles or at intervals. The term solvent rates leaving the impurity. as used herein includes solvents containing an The sponging is not as eflicient as is desired agent. p and frequently proves to be but a surface reac- Cleaning of a material yields a nascent sur- 20 tion wherein the stain is apt to again become face by thus exposing a new or fresh surface of visible. Agitation and/or mixing of a porous 'the material and of colored portions of a stain material with a fluid is invariably inconvenient, contained thereon. I have found it advisable and requires the treatment of all parts of the to add a bleaching agent to such cleaned sursurface alike and is more costly. This method is faces. It thus acts without appreciable lapse of 25 very hazardous when a flammable solvent is used time. especially in view of the large amount of solvent Rays such asmay be emitted from an ultrainvolved. violet ray tube influences the color and occa- My invention involves positive motion of a sionally the ultimate solubility of substances. solvent through the pores of the material such Such rays or other effects may be formed or gen- 30 as woven cloth with pores or other similar or erated at a convenient point. For example, gaseequivalently acting porous material which simi- 'ous fluid may be treated as disclosed in my aplarly takes common stains and/or collects partiplications Ser. Nos. 294,141, 433,704 and 449,338. cles of dirt which adhere thereto and which ma- My p ss i d s pp a of su h a s t terial is of organic matter and flexible, the moaid in the removal of colored stains and also to 35 tion, solvent action and direction of flow rapi pr ve olor. The ray may act indirectly and idly causing removal of the stain by reason of be formed within the fluid which treats the solution and velocity. By pores is meant the inp rous material or the rays may be formed at terstices or spaces between parts of the material the region of treatment and so act directly. With such -'as tubular openings or fissures. In my indirect action the actual performance is prob- 40 process, the passing or flow of a cleaning fluid ably due to ionization of the fluid, other like is made positive by pressure. The direction of methods of producing such ionization or equivaflow is preferably into the surface opposite that lent action I consider as being the equal of treatwhich first became contaminated and/or that ment with ray. v

which is most heavily saturated with the stain. In cleaning a limited area the Part surround- 45 Theexpressionorpreflx contra to indicates that ing the cleaned spot may be appreciably soiled the direction of flow is thus. This prevents furand thereiore'of a diiferent color by comparison.

ther impregnation of non-contaminated por- To correct the resulting appearance, I have found tions-of the porous material, with the stain. It it advantageous to treat the border of the first likewise prevents colloids or suspended subarea to a lesser degree as by sponging or passtances from being rubbed. or otherwise forced sage of a less effective flow of a solvent Likeintothe pores as'is the case with the common wise the eye may be deceived by making thecbormethods. The amount of solvent involved is der of the area irregular as for example like a small. many pointed star which limits the action to a w To facilitate solution of stains or other concontrolled area. The so-formed blending edge causes the change in appearance to be gradual and therefore less noticeable. This blending effect makes it possible to remove heavy stains from partially soiled materials without emphasizing the degree of soil.

Gaseous fluids such as ozone-containing air which are ionized or will ionize to yield active portions and steam .may be used to assist in cleaning. These are preferably controlled as to temperature, amount and velocity.

If it is desired to give a color to the porous material the process may be operated to allow a dyeing agent to contact therewith. In this case it is generally preferable to first clean the sur-'- face and to subsequently pass a dyeing agent through the area cleaned. This method of dyeing porous material has considerable advantage including thoroughness of applying the color and uniformity. The dyeing step may involve passage of two or more fluids through the porous material. The ordinary method of dyeing a limited area involves printing which does not give uniformity throughout the thickness.

The illustrations show means by which one modification of my invention may be carried out. Figure 1 is a side view of the apparatus, the

fabric holding device being shown partly in section and on a. larger scale than the rest of the apparatus. Figure 2 is a plan view of the diaphragm of the cloth holding device and parts immediately below it, parts being broken away.

A piece of porous material I which may be cloth or other piece of fabric to be cleaned is clamped or held between circular jaws 2 and 3 which are adapted to swing and operate about pivot 4, the counterweight 5 being used to facilitate operation and clamps not shown being used to hold the jaws tight together or in an open position. Gaskets 6 and l are used to make a tight connection between the jaws, the porous material and the porous support 8 which may be comprised of a screen of appropriate mesh, voids in the outer edges of which are filled in, to form a smooth contact with gasket 1. The supporting screen is selected so as to aiford like flow through all portions of the cloth or other porous material in the line of flow. It is preferred that the mesh of the screen approximate the mesh of the cloth or be of the same general order and kind as illustrated'. As an example a finely woven fabric would be supported by a finely woven screen. Perforations with dead areas between holes are not suitable for any but very coarse weaves. A sample of about the weave or porosity to be treated is preferably tried out to determine whether the flow is substantially uniform throughout the line of flow so that the cleaning will be uniform.

The chamber 9 is filled with a fluid under pressure with the respect to fluid contained in chamber Hi. This causes such fluid to pass through a limited area contained within the blending edge ll of the disc I! shown in detail in Fig. 2. I call or designate the optical effect, so obtained by the disc II with its extended points or distended edge, blending. The shape need not be regular or symmetrical but should be such as to gradually reduce the area, of outwardly successive annular increments, to zero. The piece of goods is so placed as to yield flow in contra direction as regards the direction of attachment or flow. of the contaminating substance (s).

-The fluid, in passing through the porousmaterial i, will remove stains and other forms of contamination therefrom which may be contained aooascs edges II. The use of this disc or its equivalent insures permanency of the optical effect which yields gradual change as between the cleaned area and other area which may be somewhat soiled. The liquid in being forced through the material permanently cleans to the imposed shape and this is in contrast with sponging which is but a by solution or mechanical movement, it is forced into chamber I 0, through outlet i3 and into a receiver l4 wherefrom it may be forced as by means of a pump 55 through a filter 66 into storage tank H. The purification by filtration in I6 may be supplemented by or substituted for by settling orcther separation means.

If the cleaning liquid which is passed from the porous material I and chamber i 0 is to be wasted or used or stored externally tothe process it may be discharged as from ,line 22 such operation being controlled as by means of valves 23 and 24. These valves may also be used to assist in the control of the pressure within chamber iii. The line 22 may also be used to pass a fiuid into chamber l0 and then discharged as from an opening in jaw 3 not shown or through line i8.

- Vapors and other gaseous fluids other than ordinary air or hot air or the like, such as those obtainable by connecting to the discharge line from a pressure operated ozone generator, may be passed into chamber 9 by means of the connection I8 and actuating of valves is and 20. The connections may be made in the well known manner so that a multiplicity of liquids and/or fluids may be used, thus for example, a number of elements l4, i5, i6, I! and I8 may be provided with appropriate piping and control valves so that two or more solvents and/or one or more gaseous fluids may be used. Likewise agitated, heated or other tanks may be provided for purposes such as mixing or preparing the solvent or dyeing agent. The inlet 2| to chamber 8 is preferably made of flexible metallic tubing. Fluid contained within chamber 9 may be under'static head due to elevation of tank i1 or to the static head plus a pressure head developed as by means of pump ii.

For some parts of the operation such as drying, liquid contained within the porous material contacting chamber I0= may be removed by imposing a subatmospheric pressure on chamber ID. This may be supplemented by the application of heat such as may be produced by heating elements not shown but located in the vicinity or as by heating gaseous fluid passed into chamber 8 from the inlet 2|.

The shapes of the jaws 2 and 3 and the disc I! with its blending edge i I may be varied as desired for the removal of stained portions of various shapes. The arrangement of the supporting screen 8, gaskets 8 and i and other mer I do not limit my claims to the number of within the limited and controlled area within the which comprises applying a cleaning fluid at a selected zone of contamination, and flowing the fluid in substantial uniformity through a limited which comprises rigidly supporting the fabric on a free draining member which will afi'ord drainage of applied solvents from substantially all portions of a selected area of the fabric, placing the surface of greatest contamination of a soiled spot of substantial size against the free draining member in a manner that the spot is circumscribed by a plate designed to confine flow of ap-' plied solventfto a selected area, applying an oillike solvent which will remove soil from the spot under a pressure which will afford a velocity which combined with solvent action will after a period of flow remove substantially all of the soil and which has rapidly flown through the cloth and the free draining member into a region beyond and out of contact with the fabric and so substantially removing the soil of the spot from the fabric subsequently flowing another oil.- like but more volatile solvent similarly through the fabric and removing all portions of the less volatile solvent and then removing all of the residual morevolatile solvent by evaporation to yield a .dry' clean area where the soiled spot hadpreviously existed.

4. In a process of cleaning by applying solvent to a-soiled porous surface of cloth goods, the steps which comprise rigidly clamping the goods about, a soiled portion, forcing a solvent through the goods at substantial rate and in a direction from the side of the surface which is least contaminated to the side of the surface which is most contaminated with the soil which latter side is held adjacent to a free draining member adapted to prevent substantial distortion of the goods and permit of relatively free flow of the solvent and beneath a plate with an opening controlling the area of flow, thus flowing the solvent uniformly through the portion beneath the opening of the controlling plate, so removing impurities forming the soil, flowing a second and more volatile solvent miscible with the first solvent through the so cleaned portion of the goods in the same direction as the flow of the first solvent and so removing the flrst solvent in substantially its entirety and causing the residual solvent-in the goods to be of the more volatile and so recovering the solvent of the goods easily removable,

and then removing the second solvent from the tion, flowing the fluid at appreciable velocity' and in substantial uniformity through a limited area designed to blend the so cleaned portion as regards uncleaned portions while preventing passage of appreciable amounts of fluid through neighboring areas, and subsequently flowing a dyeing agent through the so cleaned area-and so dyeing the area cleaned.

6. In cleaning and dyeing a fabric material 5 of. low porosity, the method comprising flowing a cleaning fluid uniformly and at substantial 'velocity through a selected and defined portion of the fabric material while preventing passage f of appreciable amounts of fluid through neigh- 10 boring areas and so cleaning a definedarea, flowing a dyeing agent through the same defined portion with substantial uniformity and so thoroughly and lmiformly dyeing the selected portion.

7. The process of cleaning a soiled spot froma porous fabric, comprising supporting the fabric on a free draining member, confining the I V spot on the fabric by a plate confining the flow of applied solvent to a selected area'of the 20 fabric, flowing an oil-like solvent under pressure 5 through said area, subsequently flowing a more volatile solvent through said area and thereby removing the first mentioned solvent, and finally removing the more volatile solvent by evaporation.

8. The process as in claim '1, the evaporation being effected by flowing air containing ozone through the fabric.

9. The method of cleaning fabric such as ordi nary cloth which comprises establishing a limited 7 area of the cloth containing a soiled spot, said area comprising gradually decreased areasof successively removed-from-the-center annular sections, flowing a solvent of components of the soil through the established area at appreciable velocity and substantial uniformity through all parts thereof while avoiding passage of appreci-q able amounts of solvent through neighboring areas and so substantially removing the soil and blending cleaned and uncleaned portions of the fabric.

I 10. The process of cleaning cloth which comprises applying cleaning liquid at a selected zone of contamination, flowing theliquid in substantial uniformity through a limited area, compristhe pores of said fabric in a single direction opposing that with which the soluble substance entered the fabric and with n substantial velocity in each and every pore within a defined and controlled area of the fabric while rigidly supporte ing the fabric to avoid appreciable distortion thereof andto remove substance soluble in the solvent and so clean the area and improve its appearance and thereafter forcing gas containing ozone through the fabric and so further improving the appearance of the surface of the area of the fabric which has been so treated.

12. In removing a soluble soil from, and bright; ening the surface of, a surface of cloth, the process which comprises forcing a solvent of low:

-volatility which is effective, as regal-(lathe reel-h moval of the soil, through the cloth in a direction opposing the direction of' entryof the aoiland 15 at substantial velocity through all the pores of a selected area and for a period sufflcient to remove substantially all of the soil, further puritying portions of the cloth of the selected area which has been so treated by displacing solvent wetting the cloth at the end of flow with a. more volatile solvent by flow of substantial amounts of the more volatile solvent similarly, through the cloth and subsequently improving the appearance of the so treated portions of the cloth by flowing air containing ozone through the cloth in similar the surface thoroughly and to render the improvement durable.

JUSTIN F. WAIT. 

